Bag



'March 31,1942.

. A. J.I STERLING 2,278,156 Y BAG I Filed June 2 2, 1940 INVENTO fllkerl Slew/( 2 ATTORNEYS Patente'd Mar. 3i, 1942 UNITED STATES, PATENT OFFICE- This invention relates to bags for packaging materials of various kinds, and has particular reference to bag closures.

An object of the invention is toprovide a construction 'of the mouth portion of the bag which makes it possible to close the bag permanently and securely in a simple way. and without involved operations in the way ,of folding, gluing and reinforcing to make the bag sift proof.

Another object is to provide a novel method of and means for closing and securing the mouth of a bag whereby a sift proof and reinforced closure is effected with a minimum of operations and material.

Still another; object is to provide a means for and a method of effecting-bag closures whichare adapted to employment with automatic machinery with only incidental hand operations.

A further object is to provide a strong and durable closure which is reinforced where most needed and which is nevertheless simple both in its construction and in the manner of making it. Illustrative bags and the novel features whereby the foregoing and incidental objects and advantages are attained are illustrated in the'drawing which accompanies and forms a part-of this specification, the novel features being described in said specification and pointed out in the claims appended hereto.

In said drawing: 1 Fig. 1 illustrates one form of construction of a bag mouth forming a part of and adapted for use in practicing the invention.

Fig. 2 is the same as Fig. 1 except that the former omits a feature of thelatter.

Fig. 3 shows one form of bag closure employing novel features of the invention.

Fig. 4 is a section along the line 44 of Fig. 3.

Fig. 5 shows another embodiment of the invention.

Fig. 6 is a section along the line 6-8 in Fig. 5.

Fig. '7 illustrates the stitch employed for both holding the closure, when completed and reinforcing the seam on both sides.

The bag and closure features are shown in the drawing in connection with single walled bags, but theinvention is adapted to be used in closing multi-walled bags with equal facility; and failure to mention either or both in this specification and in the claims is not to be construed as a limitation to what the drawing shows inthat respect.

The invention has to do with the mouth portion of the bag, and can be employed with both gusseted and non-gusseted bags of various sizes and kinds. Regardless of the size or kind, the body of'the bag is tubular and of flexible material which can be glued, folded and sewn, the most usual material being a single ply or multi-ply strong paper.

In forming the bag mouth portion of the bag blank shown in Fig. 1 the material is cutalong the lines l0 and II so as to make one wall longer than the other to provide a flap or extension 12. Also, the material is cut in such a manner as to provide what are, for wantof a better term, usually referred to herein as cars I3 although they are integral parts of the bag wall and extend between the edge ll) of the shorter bag wall H and the sides of the extensions 12, the purpose of these ears being to serve in the completed closure'to prevent sifting of powdery materials from the comers of the bag. These ears are omitted in the construction illustrated in Fig. 2, which construction is simpler than the one in Fig. 1, but is at the same time-a satisfactory one, particularly if the bag is to be used for holding coarser materials. The completed closures in Figs. 3 to 6 inclusive do not indicate either the presence or absence of the ears l3.

, In making the closure of Figs. 3 and 4 the extension or flap I2 is folded over in close engagement with the edge I] of the shorter wall, and is preferably fastened by adhesive against the outer face of the shortter wall. Folding along the proper line is facilitated by a preliminary creasing of the longer wall which, where the ears I3 are used, extends through or at the base of the ears as shown at IS. The folded material is then sewn as indicated generally at I 6, Figs. 4 and 5, preferably along a line which will extend through the ears l3, that is somewhere near the edge of the extension l2. Obviously the sewing may be effected first and the flap then folded 'down and'fastened with the adhesive. In sewing a novel form of stitch is employed which is explained in detail later on. It is sufficient here to say that the stitch is so constructed as to reinforce the seam at both sides and that this is done .solely by the which is used in sewing.

The term thread is used for convenience and is intended to include twine, wire or any other of the materials usual in bag sewing.

In making the closure according to Figs. 5 and 6, the extension I: and ears l3, if used, are folded closely over the edge III of the short wall It and preferably fastened by adhesive. The folded material may then be sewn as'indicated in Figs. 3 and 4 before the next step, but ordinarily that is not necessary. Usually after the folded exten- 2 r si'on l2 isfastenedagainst the bag wall by adhesive, although such fastening is not absolutely essential. the wall material is folded again so that the extension I2 is between two thicknesses of the bag material as shown in Fig. 6. Adhesive may be employed to fasten what; was formerly the outer face of the extension l2 against the outer face of the shorter wall Id. The multi-' fold of material is then sewn the full width of the bag mouthand preferably along a line which will include some part of the ears l3.

The stitching employedis' illustrated diagrammatically in Fig. l, the threads also being illustrated as loosened or separated for the sake of clarity. In making the stitch the needle punctures the bag material and draws the doubled thread I! through as'shown at J8, the travel or stroke of the needle being enough greater than the thickness of the material to form loops l9 projecting from the material. These loops are fastened at their ends by a thread 20 which is passed through the ends of the loops and under the sides of the next adjacent loops as at II in close proximity to the point where the loop emerges from the material. The thread 20 is drawn tight as an incident to or after joining the loops, thereby, in effect, tying a knot in the mouth of the needle puncture which serves to plug or seal the puncture. In addition, the three strands of thread afforded by the two sides of the loops and the thread 20 provides a reinforced seam structure along the one side of the seam.

On the other side of the seam, i. e. the side from which the needle enters the material, a

third thread 22 is passed around the sides I. of the loops l9 in close proximity with the points where the loops enter the material and are drawn tight, thus-in efl'ect tying knots in the mouths of the needle punctures. In addition to sealing the punctures around the doubled thread or sides of the loops l8, there is provided a strong reinforcement of the seam comparable to th one previously described at the other side of the seam. There is, therefore, good protection 45 against sifting as well as a strong, sturdy seam,.

due to the way in which the stitching is effected. In addition, the stitching can be effected by sewing machines constructed to form and connect the loops together by the threads 22 and 20 in the manner above described.

It is obvious, however that a suitable stitching It also will be obvious that other modifications and changes might be made, only some of which are hreinabove suggested, and it is therefore the desire not to be limited as to embodiments except to the extent indicated in'the claims which follow.

What is claimed is: v

1. A bag of the character described having its mouth closed by one or more folds of the bag material with the folds secured in folded condition by means of threaded loops through the folds and a thread tightly drawn along each side of the seam and tied around each loop where it enters and leaves the folds whereby to seal needle punctures on each side of the seam and reinforce the seam at both sides thereof.

2. A bag of the character described having its mouth closed by a sealed flap and one or more folds of the bag material at said mouth and the folds secured in folded condition by three threads, one of said threads being looped from one side of the seam through needle punctures in the material, there being a needle puncture for each loop, and the endsof the loops being tied by the second of said threads to the bases of the next adjacent loops in such manner as to construct a knot sealing each needle puncture from one side ofthe seam, and the third of said threads being tied around the two sides of the loop along the other side of the seam to construct knots adjacent to and sealing the needle punctures from the other side of the seam, said second and third threads also reinforcing the seam from both sides of the seam.

3. A bag closure comprising a sewed seam of continuous needle stitches through the bag walls around the bag mouth holding said. bag mouth closed, said stitches including a thread 100p extending through each needle puncture with the successive loops interconnected along one side of the seam at points adjacent the mouths of the needle punctures whereby to seal said mouths and reinforce the seam along the one side of the seam, and a continuous thread along the other side of the seam tied around both sides of each loop where the loop enters the needle puncture whereby to seal said needle punctures and reinforce the seam along the other side of the seam.

ALBERT- STERLING. 

